One conventional high gain amplifier uses a differential stage coupled to a single ended converter such as a current mirror and a voltage gain stage as disclosed in U.S. Pat. No. 4,857,862. A feedback circuit senses the voltage gain stage current and adjusts the differential stage bias to maintain the load presented by the differential-to-single-ended-converter equal to the load presented by the voltage gain stage. Such amplifiers work well and provided substantial gain. However these amplifiers have a shortcoming: the common mode range of the differential input cannot include either extreme of the supply voltage. That is, when the common mode inputs approach one of the supply voltages the input differential stage becomes cut off and when the common mode inputs approach the other of the supply voltages the differential stage goes into voltage saturation because of the circuitry which is necessarily between it and the power supply. This is so because the bias circuit is disposed between the differential amplifier and one power supply rail and the signal output of the differential stage is disposed between the single ended converter and the other rail of the power supply.